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For a long time, Dolichopoda palpata was the only species of this genus thought to live in the cave habitats of the Calabrian region. The results of our study, based on morphological and molecular data, highlight the existence of three species in the Calabria region. In particular, our data demonstrate the occurrence of two well-separated species, one in the northern Tyrrhenian area and one in the Calabrian Ionian area, attesting to the validity of D. calabra Galvagni 1968, and the discovery of a new species, D. apollinea sp. nov. Both species appear to be geographically very limited. Dolichopoda calabra occurs in the mountain region between Scalone Pass in the north and the Savuto Valley in the south (a district called 'Catena Costiera'), whereas D. apollinea sp. nov. appears to be distributed on the eastern slope of Pollino Massif. On the other hand, D. palpata shows a vast distribution, occurring in caves from La Sila in the north to the Aspromonte Massif in the extreme south of Calabria. About 1/3 of the Italian Dolichopoda species are present in this relatively small geographical area, supporting the importance of Calabria as a geographical region characterised by a high level of biodiversity. It shows the maximum values of genetic diversity and species richness in comparison with the rest of the Italian peninsula. This fact could be related to the palaeogeological and palaeoclimatic history of the region, as it was affected by glaciation events and eustatic movements. The combination of these two conditions that occurred during the Pliocene and Pleistocene transformed the Calabria into a vast archipelago of little islands, favouring the isolation of populations and the consequent speciation processes. [ABSTRACT FROM AUTHOR]

• The molecular phylogeny of the cave crickets belonging to the Rhaphidophoridae was reconstructed. • The monophyly of each assayed subfamily were supported. • Rhaphidophoridae originated in the Cretaceous period during the Mesozoic era. • The ancestral area was located both in the northern and southern hemisphere. • Fragmentation of Gondwana and Laurasia played a role in the diversification process. We investigated the molecular phylogenetic divergence and historical biogeography of cave crickets belonging to the family Rhaphidophoridae (Orthoptera, Ensifera). We used taxa representative of most of the regions embraced by the family, considering samples of Macropathinae from Gondwana land (i.e., Tasmania, Australia, New Zealand, South Africa, and South America); Aemodogryllinae and Rhaphidophorinae from Southern-eastern Asia (i.e., India, Bhutan, China, Philippines and the Sulawesi islands); Dolichopodainae and Troglophilinae from the Mediterranean region and Ceuthophilinae from North America. Based on previous papers, we carried out an analysis of both mitochondrial and nuclear DNA sequences considering the ribosomal RNA units 12S, 16S, 18S, and 28S. To reconstruct phylogeny, we use cladistics, Maximum Likelihood (ML), and Bayesian analyses. All phylogenetic analyses showed the same highly supported topology generally congruent with the classical systematic arrangement at the level of each sub-family but strongly disagree with previous affinity hypotheses between sub-families based on morphological characters. Our results reveal a close affinity between Asiatic and Gondwanian taxa from one hand and between North American and Mediterranean ones from the other hand. Dating estimates indicated that Rhaphidophoridae originated in the Cretaceous period during the Mesozoic era with the ancestral area located both in the northern and southern hemisphere. A possible biogeographic scenario, reconstructed using S-DEC with RASP software, suggested that the current distribution of Rhaphidophoridae might be explained by a combination of both dispersal and vicariance events occurred especially in the ancestral populations. The radiation of Rhaphidophoridae started within the Pangaea, where the ancestor of Rhaphidophoridae occurred throughout an ancestral area including Australia, North America, and the Mediterranean region. The opening of the Atlantic Ocean promoted the divergence of North American and Mediterranean lineages while the differentiation of the southern lineages, spread from Australia, appears to be related to the fragmentation of Gondwana land. [ABSTRACT FROM AUTHOR]

In this study, we investigated the molecular phylogenetic divergence and historical biogeography of cave crickets belonging to the genus Troglophilus (Orthoptera, Rhaphidophoridae) from caves in eastern Mediterranean and Anatolia regions. Three mitochondrial DNA genes ( COI, 12S rDNA, and 16S rDNA) and two nuclear ones ( 18S rDNA and 28S rDNA) were amplified and partially sequenced to reconstruct phylogenetic relationships among most of the known Troglophilus species. Results showed a well-resolved phylogeny with three main clades representing the Balkan, the Anatolian, and the Cycladian-Cretan lineages. Based on Bayesian analyses, we applied a relaxed molecular clock model to estimate the divergence times between these three lineages. Dating estimates indicate that radiation of the ingroup might have been triggered by the opening of the Mid-Aegean trench, while the uplift of the Anatolian Plateau in Turkey and the changes of relief, emergence, and disappearance of orographic and hydrographical barriers in the Balkan Peninsula are potential paleogeographic events responsible for the initial diversification of the genus Troglophilus. A possible biogeographic scenario, reconstructed using S- DIVA with RASP software, suggested that the current distribution of Troglophilus species can be explained by a combination of both dispersal and vicariance events that occurred in particular in the ancestral populations. The radiation of Troglophilus species likely started from the Aegean and proceeded eastward to Anatolia and westward to the Balkan region. Results are additionally compared to those available for Dolichopoda, the only other representative genus of Rhaphidophoridae present in the Mediterranean area. [ABSTRACT FROM AUTHOR]

Radon represents the major source of natural radioactivity in confined environments. Despite the clear evidence of a direct association between residential exposure and human lung cancer provided by case-control studies, results relating indoor exposure and genotoxic/mutagenic effect induction are still contradictory. The present study attempts to estimate the genotoxic effects induced by exposure to radioactive radon in wild cricket populations sampled from caves where varying concentrations of radon are present. Cave crickets are also tested as possible bio-indicator organisms of genotoxic potential of contaminated residential and confined environments. Six caves in Central Italy are considered covering a broad spectrum of radon radioactivity concentration (221-26,000 Bq/m3). Dolichopoda specimens were sampled from each cave; both haemocytes and brain cells taken from individuals were tested for responsiveness to DNA damage induced by radon through the Comet assay. Specimens from the least radioactive cave, housed in controlled conditions for 60 days before analysis, were used as control group. Statistically significant increase of DNA damage was found in all groups of individuals from each cave, for both cell types. Very low values of all Comet parameters were found in control group individuals, which gave indications of a good responsiveness of the organism to the variable environmental levels of radioactive contamination. Results indicate that cave crickets represent a reliable tool for the detection of genotoxic potential induced by radioactive contamination of confined environments and can be proposed as a possible bio-indicator system for air (-radioactive) pollution related to indoor exposure. [ABSTRACT FROM AUTHOR]

Abstract: This study focuses on the phylogenetic relationships among ninety percent of known Dolichopoda species (44 out of 49); primarily a Mediterranean genus, distributed from eastern Pyrenees to Caucasus. A total of 2490 base pairs were sequenced corresponding to partial sequences of one nuclear (28SrRNA) and three mitochondrial genes (12S, 16S and COI). A relaxed molecular clock, inferred from Bayesian analysis was applied to estimate the divergence times between the lineages using well dated palaeoevents of the study areas. Molecular substitution rates per lineage per million years were also obtained for each analyzed gene. Based on the nearly complete species phylogeny, temporal patterns of diversification were analyzed using Lineage-Through-Time plots and diversification statistics. Alternative hypotheses about the colonization of present range by Dolichopoda species were tested by means of Approximate Bayesian Computation analysis. Results from this analysis carried out on the 90% of known Dolichopoda species confirmed the previous ones based on subgroups of species, suggesting the ABC analysis as a remarkable tool in biogeographic studies. Based on these results, the distribution of Dolichopoda species appears to have been shaped by the palaeogeographic and climatic events that occurred from Late Miocene up to the Plio-Pleistocene. Both vicariance and dispersal events appear to have influenced Dolichopoda species distributions, with many processes occurring in ancestral epigean populations before the invasion of the subterranean environment. [Copyright &y& Elsevier]

Abstract: This study focuses on the phylogenetic relationships among a number of West-Mediterranean cave crickets species belonging to Dolichopoda; primarily a Mediterranean genus, distributed from eastern Pyrenees to Caucasus. In this paper, 11 Dolichopoda species from the French Pyrenees (D. linderi), the island of Corsica (D. bormansi and D. cyrnensis), and northern, central, and southern Italy (D. ligustica, D. schiavazzii, D. aegilion, D. baccettii, D. laetitiae, D. geniculata, D. capreensis, and D. palpata) were studied. Two more species, one from the Caucasus, D. euxina, and one from Greece, D. remyi, were also included in the analyses, together with more distant species within the same family to be used as outgroups. Fifteen hundred base pairs of mitochondrial DNA, corresponding to the small subunit of the ribosomal RNA (16S rRNA) and to the subunit I of the cytochrome oxidase I (COI), were sequenced in order to clarify the phylogenetic relationships and biogeography of this group of Mediterranean cave crickets. The molecular data are congruent with a phylogeographic pattern; with the geographically close species also the most related ones. Based on mtDNA divergence, the present-day distribution of genetic diversity seems to have been impacted by climatic events due to glacial and interglacial cycles that have characterized the Pleistocene era. [Copyright &y& Elsevier]